Bergmann, Peter G., et al.
Text: "J8. The Hamiltonian of Einstein's theory of gravitation with electromagnetic field." In "Proceedings of the American Physical Society. Minutes of the meeting at New York, Feb. 2-4, 1950." Physical Review. Series 2, 78(3), May 1, 1950. p. 329.
See Also: foundations of physics, gravitation.
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